Messi was sent off toward the end of the first half of the third-place playoff in Sao Paulo and refused to take part in the medal ceremony, the Guardian reported.
The Barcelona player was dismissed following a confrontation with the Chilean midfielder Gary Medel, who was also shown a red card.
Messi appeared to have been hard done by, with Medel appearing to push his head toward the Argentina playmaker as they squared up, chest to chest. The Argentina captain suggested he had been singled out following his comments about “crazy” officiating in the wake of their 2-0 semifinal defeat by Brazil in Belo Horizonte.
“We don’t need to be part of the corruption that we’ve suffered at this tournament,” Messi said, as quoted by Spanish media outlet AS. “Medel is always right at the limit. With a yellow that would have been the end of it for both of us, but well, maybe what I said recently had an impact.
“What’s important is that the team finished well in the tournament. Maybe this was ordered and I ended up suffering because of what I said.”
CONMEBOL, South America’s football confederation, said a “fundamental pillar of fair play is to accept the results with loyalty and respect”.
Its statement, which did not mention Messi by name, added, “The same goes for refereeing decisions, which are human and will always be improvable. It is unacceptable that as a result of incidents typical in competitions, involving 12 teams, all on equal terms, unfounded accusations have been launched that lack the truth and question the integrity of the Copa America.
“These accusations represent a lack of respect for the competition, all the participating players and the hundreds of professionals of CONMEBOL, an institution that since 2016 has been working tirelessly to make transparent, professionalize and develop South American football.”
Messi’s red card was only the second red card of his career, the first also coming while playing for Argentina on his debut against Hungary in 2005. The referee showed seven yellow cards in a match that was broken up with 37 fouls.
Messi had helped set up an early goal for Manchester City’s striker Sergio Agüero, with Argentina going 2-0 up through Paulo Dybala.
Chile was handed a way back into the match following a controversial VAR review which resulted in a penalty being awarded after Argentina’s Giovani Lo Celso was adjudged to have fouled Charles Aranguiz.
Arturo Vidal dispatched the spot-kick.